OS for smart card microprocessor chips

Every smart card requires an operating system. It is the hardware-specific firmware which provides basic functionality such as secure access to on-card storage, authentication and encryption. The smart card's Chip Operating System (frequently referred to as COS; and sometimes referred to as the Mask) is a sequence of instructions, permanently embedded in the ROM of the smart card. Like the familiar PC DOS or Windows Operating System, COS instructions are not dependent on any particular application, but are frequently used by most applications.

Chip Operating Systems can be segmented into two categories:

• The general purpose COS which features a generic command set in which the various sequences cover most applications, and
• The dedicated COS with commands designed for specific applications and which can even contain the application itself. An example of a dedicated COS would be a card designed to specifically support an electronic purse application.

The baseline functions of the COS which are common across all smart card products include:

• Management of interchanges between the card and the outside world, primarily in terms of the interchange protocol.
• Management of the files and data held in memory.
• Access control to information and functions (e.g. select file, read, write, and update data).
• Management of card security and the cryptographic algorithm procedures.
• Maintaining reliability, particularly in terms of data consistency, sequence interrupts, and recovering from an error.
• Management of various phases of the card's life cycle (that is, microchip fabrication, personalization, active life, and end of life).

IRIS has developed two types of COS for smart card chips. The unique features of IRIS’ single application COS (I-COS) and multi-application COS (M-COS) are that they are readily portable to any of the chips available in the market and they are able to operate on either a contact or a contactless interface. Both of these COS are open yet offer advanced security features to ensure that the information carried in the cards are well protected and are only accessible to properly authorised devices.

With I-COS, M-COS and other COS alternatives, IRIS is in the position to offer microprocessor based smart cards to accommodate any possible applications all residing in one card.